Method of making sheet-metal elbows.



No. 743,050. PATENTED NOV. 3, 1903.

' r w. c. WINPIELD.

METHOD OF MAKING SHEET ETEL ELBows.

APPLICATION FILED FEB. 7. 1903.

N0 MODEL.

ATTEET I ma @VIENTEE. V

- BY 4, ATE? UNITED STATES i Patented November 3, 1903.

PATENT OFFI E.

METHOD OF MAKING SHEET-METAL ELBOWS.

SPECIFICATION forming part of Letters Ia tent No. 743,050, dated November 3, 1903. Application filed February 7, 1903. Serial No. 142,336. (No model.)

To all whom it may concern:

Be it known that I, WILLIAM C. WINFIELD, a citizen of the United States,residing at Warrec, in the county of Trumbull and State of bows substantially as shown and described,

and particularly pointed out in the claims.

In the accompanying drawings, Figure 1 is a representation of a series of joint sections or parts in their original shape after having been cut from suitable metal tubing or otherwise made of the requisite shape for use. Fig. 2 shows an end elevation of one of said sections after it has been corrugatedlengthwise, which is the next step as to each and all the sections, and all are alike in this particular in this step of manufacture. Fig. 3 shows the same series of parts or sections as Fig. l; but in this view the said sections'after having been corrugated are distended or rounded again, substantially as they were originally, at their adjacent ends, so as to prepare them for the fourth step in the method. Fig. 4 shows the adjacent ends of two of the sections fashioned for seaming one upon or with the other, and Fig. 5 shows said ends as they appear after being interlocked and ready to be rolled or pressed down into permanent connection. Fig. 6 shows a complete elbow with the four sections thereof united, as in Fig. 5, and with the seams flattened down; and Fig. 7 shows the said elbow rolled to a finish, with the corrugations developed across the seams and made continuous from end to end of the elbow, as plainly seen.

It has been observed that the elbow thus shown and described is essentially a jointed structure in contradistinction of those common forms of corrugated elbows which are made throughout of a single piece of tubing, and the advantage that comes of my construction over the old forms is material and distinguishing, especially in that I get a much greater strength than is possible with a single-piece elbow. To these ends and in carrying out the invention I employ several distinct steps of manufacture, and in the first of these I prepare or cut sections of tubing or pipe 1, 2, 3, and 4, with their ends shaped substantially as shown in Fig. 1, to produce a right-angled elbow, as in Fig. 7; but if I want ed only half as much bend I could use only one of the sections 2 and 3, which are alike. The next step is to provide all the sections with lengthwise corrugations, and the corrugations of straight sections 1 and 4 may be formed by. rolling the full length therein, while theintermediate sections are perfectly corrugated in dies and bent and corrugated at the same time. The next step is to take the corrugations out of the adjacent ends of the several sections or joints, so as to even said ends and bring them back to their original rounded shape, while the corrugations are left standing in the bodies of the sections, as seen in theseveral views, Fig. 3. Having these things done, I proceed next to construct said ends relatively asseen in Fig. 4, in which one end a isexpa'nded or enlarged all around sufficiently to admit the reversely bent end 11 of the other section. This latter bend also extends entirely around the section and forms a hook-shaped back lap on the outside of the section adapted to be engaged as in Fig. 5. It is seen in Fig. 4 that the end or extremity a, overlaps and extends beyond hook b far enough to be turned in and constitute a hook itself engaged with and beneath hook b relatively as seen in Fig. 5, thus efiectually interlocking the sections or joints with a seam four deep. When this connection has been made, the said sections are gone over again circumferentially at the seams and the said seams are rolled, pressed, or otherwise forced together and substantially flattened even with the adjacent end. Then and finally the elbow is recorrugated or the corrugations are carried into and across the seams also, and thus an elbow of exceptional strength and value is produced. With suitable machinery the flattening down of the interlocking ends and rolling of the corrugations into said connections may be accomplished at the same time, and either rolls or dies may be employed for this purpose.

Obviously while I show a tubular or cylindrical shape of elbow in cross-section I may make other shapes of varied cross-sectional pattern and keep Within even what are known as equivalent constructions of product and by the practice of identically the same invention in their manufacture.

It is practicable to corrugate the sections or joints between their ends relatively asseen in Fig. 3 and have the ends uncorrugated; but I prefer the method or practice of full-length corrugation first and evening the ends as a third step. The corrugations themselves may be of any cross-sectional pattern, whether round or angular, or more or less of both. They are shown in this instance as round or segmental,

What I claim is 1. The. method of making jointed sheetmetal elbows, which consists in first forming the several sections to the required shape; then corrugating the same and evening the ends, and at last seaming the said ends together and corrugating across thescams, substantially as described.

2. The method of making a sheet-metal elbow comprising several sections, consisting in corrugating each section separately and fashioning one or both ends thereof to be interlocked with one of the ends of another section, and finally compacting the joints so made and corrugating across the same in harmony with the corrugations in the body of the several sections, substantially as described.

3. The method of making corrugated and jointed elbows, the same consisting in shaping and corrugating' each section separately, then interlocking the meeting ends of the sections one upon the other and at last corrugating the uncorrugated portions of th elbow, substantially as described.

Witness my hand to the foregoing specification this 22d day of January, 1903.

WILLIAM C. WINFIELD.

Witnesses:

G, W. BYARD, A. G. JUDD. 

